simple model of the atom

paper 1

compound

a pure substance made up of 2 or more elements chemically bonded and cannot be separated by physical means

ionic

metal and non metal

covalent

nonmetal

metallic

metals

the law of conservation of mass

there must be the same number of atoms on either side of the equation

half equations

represent only half of whats happening in a reaction involving electron transfer

one loses

one gains

ionic equation

used to indicate what happens to ions during reactions

mixture

a combination of 2 or more substances that aren’t chemically bonded together

filteration used to

separates an insoluble solid from a mixture of a solution

filtration method

1. filter paper placed in a filter funnel above a beaker

2. the mixture of insoluble solid and liquid is poured in

3. only liquid particles pass through and soluble solids

4. the filtrate is left

crystallisation used to

separated dissolved solid from a solution

crystallisation method

1. solution is heated

2. the solvent evaporates leaving a saturated solution

3. the solution cools slowly

4. the crystals are collected

distillation used to

separates a liquid and soluble solid from a solution

simple distillation method

1. solution heated and pure water evaporated producing a vapour

2. vapour passes through condenser and cools and condenses turning into pure water

3. only solid solute is left behind

fractional distillation method

separates 2 or more liquids that are miscible

1. solution heated to the temp of substance with lowest bpt

2. substance will rise and evaporate and vapours cool and condense

3. leaves other components

1897

thomson plum pudding

1909

rutherford model

1913

bohr model

1932

current nuclear model

rutherfords scattering experiment

in 909

1. rutherford shot a beam of positive particles to gold foil

2. some scattered but some deflected directly back

3. discovered nucleus

4. atom is mainly empty space

0.1nm

radius of atom

relative atomic mass

(% of isotope x mass) a + b / 100